Time for summer coolant ratio advice

[Vangruver]

I went to my local VW parts supplier and found out that G11 is becoming more and more scarce. Well to this supplier that is. So i bought G12

In any case, i had already performed a 3 stage flush.  water > solution > water > water then mixed up 50/50 G12 and distilled and started driving

THEN my heater core started leaking.

So i bypassed it, and pulled out all the new coolant. Within 48 hours of the new stuff. No big deal. I'll replace the core come september.

After bypassing it, i refilled with 50/50 mix again.

I don't have an external water temp gauge, I'd like one, but for the time being, i trust the gauge on the dash and listen to the water temp sensor to kick in the coolant fan.

Story to end with a question.....

Would I be better off running a 60/40, or 70/30 for the next 3 months?

I plan on doing a LOT of road trips this coming summer as there are car shows ALL OVER the pacific north west, and i will be excited to check them all out.

[dieselweasel]

50/50 is the ideal mix for most conditions.  I don't see the need to use VW-specific coolant either.  IMO, a heavy duty extended life coolant such as Cat ELC is the best stuff out there.

[bajacalal]

From what I've read, antifreeze has less cooling capacity than water (water is a better conductor and absorber of heat) so you are better off using less antifreeze and more water. So put enough antifreeze in your system to give you adequate protection for the coldest place you travel which I don't think will be more than 50% if you stick to the coastal PNW.

[Vangruver]

the G12 that i bought was fairly cheap.

And now that I will plan on doing another coolant change, since I have to replace the heater core, I "may" look into something other than the G12.

I think i might lean towards a 70/30 mixture [water/coolant] and then I should have enough from a 4 liter bottle to do the winter ratio of 50/50

just curious what some of you might be running in the warmer climates

[bajacalal]

50/50. It's what I have always done, more so for lubrication and corrosion protection. There's a lot of aluminum in a VW.  It's 91F at my house right now. The coldest I expect my VW to see is low 20s. It's hot and sunny and I don't like it. I wish it would just rain. I should move to your part of the world.

I think that changing your coolant every 6 months is excessive and that you are making extra work for yourself for no real reason. Use the manufacturer specified ratio that corresponds to your climate. This is usually 50/50. I also use some type of extended life antifreeze for everything. I think it makes a noticeable difference in the amount of corrosion you find in the system.

Are you actually experiencing overheating problems in hot weather? I don't think you are going to see but a small difference due to the ratio. IIRC there is more than one radiator size that fits our cars. Use the largest (Passat???) one. Use an oil cooler. Get a less restrictive exhaust. Dual fans. How about wiring up a manual fan control switch? These make a noticeable difference.

[Vangruver]

50/50. It's what I have always done, more so for lubrication and corrosion protection. There's a lot of aluminum in a VW.  It's 91F at my house right now. The coldest I expect my VW to see is low 20s. It's hot and sunny and I don't like it. I wish it would just rain. I should move to your part of the world.

I think that changing your coolant every 6 months is excessive and that you are making extra work for yourself for no real reason. Use the manufacturer specified ratio that corresponds to your climate. This is usually 50/50. I also use some type of extended life antifreeze for everything. I think it makes a noticeable difference in the amount of corrosion you find in the system.

Are you actually experiencing overheating problems in hot weather? I don't think you are going to see but a small difference due to the ratio. IIRC there is more than one radiator size that fits our cars. Use the largest (Passat???) one. Use an oil cooler. Get a less restrictive exhaust. Dual fans. How about wiring up a manual fan control switch? These make a noticeable difference.

Not that I want to change the coolant every 6 months...it's more so the fact that after i swapped over to the coolant, from a flush. I experienced my heater core leaking.

Since I don't want to do the work right now, i did something simple which was bypassing the entry and exit hoses from the heatercore entry on the firewall.

The car runs totally fine. No overheating, the coolant sensor turns on the fan when it's supposed to. The thermostat is a hotter one, and the waterpump runs just nicely.

Without having a proper external temp gauge, the dash mounted temp gauge is reading the coolant at the midway mark.

In the city, The sensor kicks in the fan at just above that, and sometimes when it's continuous stop and go traffic it gets to as high as the 3/4 bar but never higher. It's annoying because the fan runs constantly. It's doing it's job that's for sure!

When I was running straight distilled during the flush it wouldn't lean that high up, however the ambient temperature then was a lot cooler than it is now.

While driving on the highway, the dash mounted temp gauge would run below the midway mark, exactly how i expected it to be. Keeping the car warmish to ensure that the combustion is effective.

I've never really played around with changing of the coolant ratio, but doing a little bit of testing to find that right mix is fine with me.

It's been enjoyable working on this.....and now that i've tweeked enough to find out what works, and what doesn't it's almost on to another car

[R.O.R-2.0]

50/50. It's what I have always done, more so for lubrication and corrosion protection. There's a lot of aluminum in a VW.  It's 91F at my house right now. The coldest I expect my VW to see is low 20s. It's hot and sunny and I don't like it. I wish it would just rain. I should move to your part of the world.

I think that changing your coolant every 6 months is excessive and that you are making extra work for yourself for no real reason. Use the manufacturer specified ratio that corresponds to your climate. This is usually 50/50. I also use some type of extended life antifreeze for everything. I think it makes a noticeable difference in the amount of corrosion you find in the system.

Are you actually experiencing overheating problems in hot weather? I don't think you are going to see but a small difference due to the ratio. IIRC there is more than one radiator size that fits our cars. Use the largest (Passat???) one. Use an oil cooler. Get a less restrictive exhaust. Dual fans. How about wiring up a manual fan control switch? These make a noticeable difference.

Not that I want to change the coolant every 6 months...it's more so the fact that after i swapped over to the coolant, from a flush. I experienced my heater core leaking.

Since I don't want to do the work right now, i did something simple which was bypassing the entry and exit hoses from the heatercore entry on the firewall.

The car runs totally fine. No overheating, the coolant sensor turns on the fan when it's supposed to. The thermostat is a hotter one, and the waterpump runs just nicely.

Without having a proper external temp gauge, the dash mounted temp gauge is reading the coolant at the midway mark.

In the city, The sensor kicks in the fan at just above that, and sometimes when it's continuous stop and go traffic it gets to as high as the 3/4 bar but never higher. It's annoying because the fan runs constantly. It's doing it's job that's for sure!

When I was running straight distilled during the flush it wouldn't lean that high up, however the ambient temperature then was a lot cooler than it is now.

While driving on the highway, the dash mounted temp gauge would run below the midway mark, exactly how i expected it to be. Keeping the car warmish to ensure that the combustion is effective.

I've never really played around with changing of the coolant ratio, but doing a little bit of testing to find that right mix is fine with me.

It's been enjoyable working on this.....and now that i've tweeked enough to find out what works, and what doesn't it's almost on to another car

if you did a hotter thermostat, and kept the same fan switch, then yup, thats the result.. the t-stat opens, then a few more degrees and the fans kick on.. only way to fix it is a hotter thermo switch..

[Vangruver]

I'll consider a hotter thermo switch, or i might just go balls out, and have an bypass switch mounted within the cabin to kick in when I feel it necessary, coupled with a passat dual fan system.

who knows what I might do really. it's running really really nice right now.

[AudiVWguy]

You really can't beat water for it's thermo-conductivity properties. I would run about 10% antifreeze. After mixing you can check to see how far its rated down to. The hot set-up (pun intended) would be to add about a half a bottle of Purple Ice to distilled water. It works far better than Red Line. I tested both with a digital temp probe checking the coolant coming out of the head and found about 2-3 degrees less with the Red Line and more like a 10-11 degree difference with the Purple Ice.
Up north where you live its probably not necessary, further south, yeah, every little bit helps.
Just my 2 cents.
Cheers,
-JB

[Vangruver]

For ease and simplicity I get all components of the cooling system into good condition, run a 50/50 mix and forget about it for a couple years.  If the cooling system is functioning properly, you will not ever overheat with a 50/50 mix and you won't need to be concerned about cold temps.   

at the moment, i'm going to keep it as such.

50/50 is always been a good ratio no matter what car i drove.

and it hasn't bothered me such since i posted.

[R.O.R-2.0]

For ease and simplicity I get all components of the cooling system into good condition, run a 50/50 mix and forget about it for a couple years.  If the cooling system is functioning properly, you will not ever overheat with a 50/50 mix and you won't need to be concerned about cold temps.    

at the moment, i'm going to keep it as such.

50/50 is always been a good ratio no matter what car i drove.

and it hasn't bothered me such since i posted.

BE SURE TO KEEP ATLEAST SOME COOLANT IN THE cooling system.. my buddy is working on a honda right now because it had water in it for too long.. ate the steel coolant pipe, trashed the engine. (head is WAY WARPED)

if you dont run coolant, atleast run water wetter or something like that. im sure it has something in it to raise the boiling point, and corrosion inhibitors..

[DieselBalz]

I usually run 50/50 in my vehicles, and it is usually 85-98F with 100 percent humidity 85% of the year. Have never had an issue, but I think I might try some of this Purple Ice. I notice the needle is alot closer to the third hash mark than I would like when on the interstate and running the AC. Usually it runs just a hair to the right of middle when not running the AC. Maybe this will help it out a little.

[ricosuave]

50/50 is the ideal mix for most conditions.  I don't see the need to use VW-specific coolant either.  IMO, a heavy duty extended life coolant such as Cat ELC is the best stuff out there.

this?
http://www.cat.com/cda/files/1386276/7/PEHJ0067-02.pdf

[nathan_b]

vw/pentosin switched to g12 because it helped with cylinder head/engine corrosion. it also leaves a nice pink powder wherever it leaks. I used it in my frankenmotor caddy mixed 50/50 from right at 100f to -12f and never had one issue. No seals started leaking and am running oe heater core and copper rad.